Motor end bell structure



Dec. 4, 1956 J. R. EASTMAN 2,712,929

MOTOR END BELL STRUCTURE Filed March 31, 1955 Z FIG. :1.

2,772,929 MOTOR END BELLSTRUCTURE John R. Eastman, Pasadena, Calif., assignor to Sterling Electric Motors, Inc., Los Angeles, Calili, a corporation of California a t r Application March 31, 1955, Serial No. 498,312

7 Claims. (Cl. 308-236) The present invention relates in general to end bell structures for electric motors, or the like, and, more particularly, to a structure for assembling a motor. end bell with a bearing, preferably a ball bearing, on the armature shaft of the motor, a primary object of the invention being to provide an improved structure of this nature which is simple :and effective.

More specifically, an object of the invention to provide means for assembling the bearing and the end bell I 2,772,929 Patented Dec.4, 1956 ICC of the invention which illustrated inthe accompanying drawing and which is described in detail hereinafter.

Referring to the drawing 7 a Fig. 1 is aside elevational view of an electric motor in which the present invention has been incorporated, one

1 end of the motor being shown in section to reveal the positions, and to provide means operable entirely irom the exterior of the end bell for swinging such pivoted elements over the inner side of the bearing and for clamping them against suchinne'r side, I p l A further object of the invention is to providea struc t-ure which include-selernents pivotable" overthe inner side of the bearing, stop means on the end bell internally thereof for limiting pivotal movement of the pivoted elements, rotatable .actuating' elements extending through the end bell into; the interior thereof and rotatable tf rom'the exterior thereof, and mutilated thread means connecting the pivoted element s toflt hejactuatingelements so as'to provide resistance to rotationof the actuating elements relative to the pivoted elements, whereby rotation of the actuating elements from the exterior of the end 'bell' first swings the pivoted element-s ,oven'th'einner side of the bearing :against the stop m eans to prevent further pivoting of the pivoted elements, and then draws the pivot-ed elements outwardly against the inner side of the'bearing to assemble-hand the en-dbe'll. f-

Another object is to provide pivoted elements having holes therein into which the actuating elements are threaded, the threads'on one s'et offthese elements being mutilated for the purpose outlined above.

*Stillanother object is to providepivoted elements having threaded holes the threads in which are mutilated to I provider resistance to relative rotation of the'pivoteii elements and the actuating elementsfofthe purpo'se hereinbefore set forth; Y M 7 Still another object is to provide pivoted elements having threaded holes therein; each pivoted element having present invention, together with various other objects,

advantages and features thereof which will become apparent, may be attained with the exemplary embodiment manner in which the present invention is incorporated therein; 6 y p a i Fig. -2 is an enlarged, fragmentary, transverse sectional view taken along the arrowed line 2--2 of Fig. 1; and

'Fig. 3 is an enlarged, isometric view of one of the pivoted elements of the invention hereinbefore mentioned. Referring to Fig. 1 of the drawing, the numeral -10 designates generally an electric motor which, except for incorporating the present invention therein, is conventional. Briefiy the motor 10 includes the customary housing 12 which is provided with the usual base 14 for mounting the motor on any suitable supporting structure, not shown. The motor 10 includes a rotor 16 carried by a shaft 1 8 mounted in ball bearings one of which is shown and designated by the numeral 22. Thisbearing is carried by an end bell 26 secured to the housing 12 by one or more bolts 30, 1

The bearing 22 includes an inner race 32 and an outer race 34 separated by balls $6, the particular bearing shown bei-ng of the sealed type and being equipped with lubricant retainers 38. The inner race 32 is seated against a shoulder 40 on the shaft 18. The outer race 34 of the bearing is disposed in a recess 44 in the end bell 26 and is seated againstv an inwardly facing shoulder '46. The shaft 18 projects through an opening 48 in the end bell 26 and carries a collar 50. i

The end bell 26 is provided with bosses '52 adjacent the bearing recess '44 and through these bosses extend rotatable actuating bolts or screws '54. The screws 54 are provided with heads 56 externally of the end bell, lock washers 58 :pre'ferably' being disposed Iunder the heads The inner. ends of'the screws 54,'are.externally threaded and are threaded intoin'tern-ally. threaded holes 60, Fig.- 3, inpivoted elements or; dogs 62." The threads on the screws '54 or in [theldogsltiz a're mutilated to resist rotation of the screws relative the dogs. ln thestrueture shown, the threads in the hole601-in the 'dogs'62 are mutilated bytforming depressions 164, in the dogs 62 Lat the innerends or the holes 60. (The term inner as used herein is applied to surfaces-facing in the same direction as the inner surface of the end bell 26.) Triangular depressions 64, as shown, which are preferably formed with a triangular punch after the threads in the hole 60 are formed, provide satisfactory mutilation of the threads in the'holebfla f r Pivotal movement of thedo'gs 62 with the screws 54 asthe latter are rotatedffr'om' the exterior of the 'end bell 26 is limited by step means or stops 66 with which the dogs are 'engageable. jThl stops 766 are formed on the 'inner surfaces of the bosses SZadjacent the bearing recess 44'and adjacent the respective screws 54, thedistance between the stops scans theaxe's ofthe'screws 54 beingless than the maximum radiusfof the dogs 62.

As best showninFigsifZ i 4 'lie'; di awing, the

, hole I 60 through each dogi62'is loc ed adjacent, one

, end thereof'so as to provide 1 a short af n 68 on, one side of the hole Q r opposite side thereof, The l gth offthe hbrf'airhsf 68 sane dogs 62, measured from the' centers of the'lioles 60, is less thanthe distance from the 'axsfof the screws 54 to the bearing recess 44 so that, when the short arms 68 of the dog62 are, directed towardfthe bearing recess; the bearing 22'may1movej into such recess, the dogs 62 being disengaged frorhdhe' steps 66' under such condi tions. However, when the long arms 70 of the dogs 62 face the bearing recess 44, they are swung inwardly over the inner side of the bearing 22 and engage the stops 66, as indicated in the upper half of Fig. 2- ofthe drawing.

Considering the manner in which the bearing 22 and the end bell'26 are assembled after the bearing isplaced on theshait 18, the-end-bell is placed in the position shown. 7 As this is done,' the dogs 62 are'in the position shown in thelower half of Fig. [2 so that the bearing-may enter therecess 44therefor." With the bearing 22 in the recess 44', a suitable tool is applied to the. heads 56 of the screws 54 and these screws are then rotated to swing the dogs-=62 over the innerside of the'bearing' 22 and into engagement with the stops 66, as shown in the upper half of Fig. lot the drawing. I Such initial'rotation'of the screws 54' does not produce rotationof the'dogs'62 relative thereto d 'u'e toj the thread mutilation hereinbefore discussed; Howevcr, once the long arms 70"ofgthe ing through said end bell and operable from the exterior thereof for pivoting said pivotedelements over the inner dogs 62 overlie the inner side of thebearing 22 and V engage the stops 66; continued rotation of the screws 54 results, of course, infrotat'ion thereof relative to the dogs inopposition'to the resistance provided by the thread mutilation. Consequently, the screws 54 advance inthe threaded holes 60 in the dogs 62 to draw thedog's toward the inner side of the bearing 22 and clamp the long arms 70 thereof against the inner side of the bearing. Such rotation ofthe screws 54 is continued until the desired degree of tightness is attained, the bearing 22 and the end bell 26 then being securely assembled with the bearing in the recess 44. The end bell 26 may be bolted to the housing 12 either before or after assembling the' bearing 22 and the end be1lt26 in the foregoing manner. V

Thus,rthe present invention provides a simple and positive wayof assembling the'bearing and the'end bell without any necessity for aligning screws and holes, as has been thepractice heretofore,'it merely being nec'es sary to swing the long arms 70 of the dogs 62 out of the way to permit entry of; thebearing into its recess in the end bell. Thereupon, the screws 54 maybe rotated'to clamp the bearingfinplace. I

Although'l have disclosed an exemplary embodiment of my invention herein in an exemplary environment,

itwill be understood that various changes, modifications and-substitutions may be incorporated in such embodia ment and: that such embodiment may be utilized in other environmentsf'all without departing 'from 'the spirit ofv bination of: an end bell for an electric motor, 'said end 7 bell having an internal bearing recess therein; a bearing insaid recess; pivotable means in said end bell adjacent said recess and pivotable over the inner side of said bear ing; and means extending through said end bell and operable from the exterior thereof for pivoting said pivotable means over the inner side of said bearing,

2. In a structure of the character describedfthe combination of: an end bell for an electric motor, said end bell having an internal bearing recess therein; a bearing in said. recess; pivotable means in said end belladjacent said recess and pivotable over the inner side of said bearing; means extending through said end bell and operable from the exterior thereof for pivoting said pivotable means over the inner side; of said bearing; and means extending through said end'bell andpperablefrom the; exterior thereof for: clamping said pivotable means against the inner side of-said'bearingt V 3. In a' structur e of the character" described, the com-;

bination of an endbell for an electric motor, said end bell having an internal bearing recess therein; a bearing in said recess; pivoted elements in said end bell adja side of said bearing into engagement with said stop means and for subsequently clamping said pivoted elements against the inner side of said bearing.

4. In a structure of the character described, the combination of: an end bell for an electric motor, said end bell having an internal bearing recess therein; a bearing in said recess; pivoted elements in said end oell adjacent said recess and pivotable over the inner side of said bearing; st op means for limiting pivotal movement of said pivoted elements; screw elements extending through said end bell into the interior thereof and rotatable from the exterior thereof and threadedly engaging said pivoted elements; and rotation resisting means tending to prevent relative rotation of said pivoted elements and said screw elements, whereby rotation of said screw elements from the exterior of said end bell first swings said pivoted elements over the inner side of said bearing against said stop means and then draws said pivoted elements against the inner side of said bearing.

' 5. In a structure of the character described, the combination of: an end bell for an electric motor, said end bell having an internal bearing recess therein; a bearing in said recess; pivoted elements in said end bell adjacent said recess and pivotabletover the inner side of said bearing; stop means on said end bell'for limiting pivotal movement of said pivoted elements; rotatable actuating elements extending through'said end bell into the interior thereof and rotatable from the exterior thereof; and mutilated thread means connecting said pivoted elements to said actuatingelements, whereby rotation of said actuating elements from the exterior of said end bell first swings said pivoted elements over the inner side of said bearing against said stop means and then draws said pivoted elements against the inner side of said bearing.

6 A structure as defined in claim 5 wherein each of said pivoted elements has a threaded hole therethrough into which the correspondingoneof said actuating elements is threaded, and is provided with a depression therein at one end of said hole mutilating the threads therein. 7 7

' 7. In a structure for assembling two members oneof which is relatively inaccessible from the exterior of the other, the combination ofzj a pivoted element in said other member adjacent said one'member and pivotable over the innerside of said one member; stop means on said other member and cngageable by said pivotcdele' ment for limiting pivotal movement of said pivoted element to a position over the innerfside of said one mom: ber;'a rotatable actuating element extending through said other member into the exterior thereof and rotatable from the exterior thereof; and mutilated threads conmeeting said pivoted'ele ment to said actuating element so as to resist relative rotation of said pivoted element and said actuating element, said-pivoted element having a threaded hole therethrough and said' actuating; element being threaded into said hole, said pivoted element having a depression therein at one 'endof said hole muti- V lating the threads in said hole "at said one endthereof,

cent said recess and pivotable over the inner side of said aring; stop m ans on S i e d b ll v r l m ing Pivotal whereby rotation of xsaid actuating element from the exterior. of said othern ember first swings said pivoted element over the inner side of 'said one member and against s 1d; stop means to limit pivotal movement of 7 said pi c tel me rd hendr ws s d pivoted f ment againstthe inner side ot, said one member in 'the file of this patent UNITED STATESPATENTS' 

